From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 1 Apr 2004 02:45:28 +0200 From: Andrea Arcangeli Subject: Re: [RFC][PATCH 1/3] radix priority search tree - objrmap complexity fix Message-ID: <20040401004528.GU2143@dualathlon.random> References: <20040331150718.GC2143@dualathlon.random> <20040331172851.GJ2143@dualathlon.random> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040331172851.GJ2143@dualathlon.random> Sender: owner-linux-mm@kvack.org Return-Path: To: Hugh Dickins Cc: Andrew Morton , vrajesh@umich.edu, linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Wed, Mar 31, 2004 at 07:28:51PM +0200, Andrea Arcangeli wrote: > if they run into trouble I'll return to the pagecache API adding the > GFP_KERNEL and check for oom failure. there were troubles with the header indeed. So I went back to the pagecache version (now fixed with GFP_KERNEL and oom retval checking). the oops I've got with the header trouble was weird (but at least the previous radix_tree_delete crash is gone), so it's not completely clear if this will be enough to make it work as well as it was working before the -mm writeback changes. I tried to reproduce but apparently acpi is doing nothing here for a echo 4 > sleep :/. diff -urNp --exclude CVS --exclude BitKeeper --exclude {arch} --exclude .arch-ids x-ref/mm/page_io.c x/mm/page_io.c --- x-ref/mm/page_io.c 2004-04-01 02:09:53.846664248 +0200 +++ x/mm/page_io.c 2004-04-01 02:11:41.526294456 +0200 @@ -139,7 +139,7 @@ struct address_space_operations swap_aop /* * A scruffy utility function to read or write an arbitrary swap page - * and wait on the I/O. + * and wait on the I/O. The caller must have a ref on the page. */ int rw_swap_page_sync(int rw, swp_entry_t entry, struct page *page) { @@ -151,8 +151,11 @@ int rw_swap_page_sync(int rw, swp_entry_ lock_page(page); BUG_ON(page->mapping); - page->mapping = &swapper_space; - page->index = entry.val; + ret = add_to_page_cache(page, &swapper_space, entry.val, GFP_KERNEL); + if (unlikely(ret)) { + unlock_page(page); + return ret; + } if (rw == READ) { ret = swap_readpage(NULL, page); @@ -161,7 +164,12 @@ int rw_swap_page_sync(int rw, swp_entry_ ret = swap_writepage(page, &swap_wbc); wait_on_page_writeback(page); } - page->mapping = NULL; + + lock_page(page); + remove_from_page_cache(page); + unlock_page(page); + page_cache_release(page); /* For add_to_page_cache() */ + if (ret == 0 && (!PageUptodate(page) || PageError(page))) ret = -EIO; return ret; -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: aart@kvack.org